So I just recently got the Hero 3 and I've used it on one trip so far. I have 1 extra battery but 2 batteries is not enough to last the whole day. So I'm thinking I need another battery, but I was wondering if the battery bacpac will last longer than another battery. The bacpac is 50$ while a battery is only 20$. Any thoughts or suggestions?

BTW: I only get a little over an hour of battery, which isn't shit but I guess it is what it is.

Well the battery bacpac is supposed to give you up to 2x the power. So basically it's the same as having a spare battery. I think it would be better to keep as many spare batteries as necessary in your pocket/pack so that you don't have to add weight/bulk to the camera. It only takes a few min. to change out right? Unless you're doing something that you need to shoot uninterrupted for a long time, shouldn't be that big of a deal.